It is found that most motor-driven devices utilize a multi-stage switch to control the rotational direction of the motor and have no braking means. Hence, the operator has to wait until the device is completely stopped before he can carry out the next operation hence wasting time, decreasing production efficiency as well as increasing cost. It is, therefore, an object of the present invention to provide a controlling mechanism for a direct current motor which may obviate and mitigate the above-mentioned drawbacks.